Trouble entering a world in realms

For a few weeks, I've been playing in this world that a friend of mine, put in realms, and that's ok, some lag, but usual.
Now, I woke up a day, and I just can't go in anymore, don't appear to me the option to enter the world, and I still in the realms, so, it's a bug, I play in the android version, and can't figure out a solution.